From: Denis de Bernardy Date: 2012-02-17T04:09:06+09:00 Subject: [ruby-core:42690] [ruby-trunk - Bug #5759] flatten calls to_ary on everything Issue #5759 has been updated by Denis de Bernardy. Possibly related: http://bugs.ruby-lang.org/issues/6039 ---------------------------------------- Bug #5759: flatten calls to_ary on everything https://bugs.ruby-lang.org/issues/5759 Author: Thomas Sawyer Status: Open Priority: Normal Assignee: Category: Target version: 1.9.3 ruby -v: ruby 1.9.3dev (2011-09-23 revision 33323) [x86_64-linux] I often ensure that I have an array by doing: def foo=(x) @foo = [x].flatten end But this has turned into a problem as of late, as it seems #flatten is calling #to_ary on every element in the array, and apparently catching the error raised if #to_ary isn't defined for that object. But that causes potential issues with objects that use #method_missing. I think #flatten should use `respond_to?(:to_ary)` to make sure an object can handle it before actually calling it. -- http://bugs.ruby-lang.org/